depends what I'm going out, my walkabout kit; a cleaning cloth and lens pen, If I've got my big bag then my
rocket blower, I also carry a notepad and pen (useful for recording stuff), spare memory card, spare set of AA batteries for my flash.
If I've got my big bag then I'll carry a selection of filters; filters really depend on what you're shooting a PL is worth investing in and quality does vary between brand, a UV filter will lose you about 1/3 of a stop but will help reduce haze and protect your lens from being fouled. ND filters are needed if you plan on doing long exposure (wide aperture) daytime shots (these are also good for bring the shutter speed down for flash (fill in) photography on bright days).
I don't always carry my remote as If I'm walking about I don't always have my tripod or gorilla pod, but for tripod work they are "essential" the work around is a very short self timer but this wont work in all situations.
A torch is always handy to carry good for inspecting your lens, changing lens finding the buttons etc.
Strobist gels and velcro for attaching them (you probably wont need these yet).